Top PDF Notch is required in adult Drosophila sensory neurons for morphological and functional plasticity of the olfactory circuit.

Notch is required in adult Drosophila sensory neurons for morphological and functional plasticity of the olfactory circuit.

Notch is required in adult Drosophila sensory neurons for morphological and functional plasticity of the olfactory circuit.

Our characterization of this circuit allowed us to manipulate components of the N pathway in synaptic partners and ask what effect these manipulations had on long-term odor induced neu- ronal plasticity. In the absence of Dl, N does not undergo the proteolytic cleavages required for its activation via the canonical pathway (Fig 1B). Therefore, loss of Dl in the PNs should have the same phenotype as the loss of N in ORNs, i.e. reducing Dl in VA6 PNs should block the in- crease in volume of VA6 in response to GA. To test this, we drove expression of control (mCherry) or Dl RNAi in VA6 PNs and used a direct fusion of CD8-GFP to the Or82a promot- er (Or82a-CD8-GFP [48]) to measure the volume of VA6. Flies were exposed to air or GA as in Fig 2. As in Fig 2E, the volumes of all the glomeruli were normalized to the median volume of the glomeruli of air exposed flies. The normalized volumes of the GA exposed flies (controls in purple and experimentals in blue) are presented in Fig 6A. (The plots of the air exposed flies are not depicted in the figure. The entire data set is presented in S4 Fig). Whereas knockdown of N in VA6 ORNs (Fig 6A, lane 2) prevents the increase in glomerular volume that would oth- erwise result from prolonged GA exposure (Fig 6A, lane 1), Dl knockdown in VA6 PNs (Fig 6A, lane 14) fails to prevent this increase (Fig 6A, lane 13). Indeed, the increase in VA6 volume is larger in GA exposed flies that express Dl RNAi in PNs (Fig 6A, lane 14) than in flies that ex- press mCherry RNAi in PNs (Fig 6A, lane 13). These data indicate that Dl in PNs is not re- quired to activate N in ORNs to promote the volume increase, and that to promote the volume increase N is not acting via the canonical pathway. The fact that VA6 was larger in GA exposed flies lacking Dl than in GA exposed control flies indicates, rather, that the role of Dl in PNs is to limit the extent of the volume increase. These results raise the possibility that prolonged ex- posure to GA operates through a non-canonical N transduction pathway to promote the in- crease in VA6 volume, and that this output is constrained by Dl signaling from PNs, conceivably via activation of the canonical N pathway.
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Caspase inhibition in select olfactory neurons restores innate attraction behavior in aged Drosophila.

Caspase inhibition in select olfactory neurons restores innate attraction behavior in aged Drosophila.

Sensory and cognitive performance decline with age. Neural dysfunction caused by nerve death in senile dementia and neurodegenerative disease has been intensively studied; however, functional changes in neural circuits during the normal aging process are not well understood. Caspases are key regulators of cell death, a hallmark of age-related neurodegeneration. Using a genetic probe for caspase-3-like activity (DEVDase activity), we have mapped age-dependent neuronal changes in the adult brain throughout the lifespan of Drosophila. Spatio-temporally restricted caspase activation was observed in the antennal lobe and ellipsoid body, brain structures required for olfaction and visual place memory, respectively. We also found that caspase was activated in an age-dependent manner in specific subsets of Drosophila olfactory receptor neurons (ORNs), Or42b and Or92a neurons. These neurons are essential for mediating innate attraction to food-related odors. Furthermore, age-induced impairments of neural transmission and attraction behavior could be reversed by specific inhibition of caspase in these ORNs, indicating that caspase activation in Or42b and Or92a neurons is responsible for altering animal behavior during normal aging.
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Drosophila Avoids Parasitoids by Sensing Their Semiochemicals via a Dedicated Olfactory Circuit.

Drosophila Avoids Parasitoids by Sensing Their Semiochemicals via a Dedicated Olfactory Circuit.

We next identified the olfactory sensory neuron(s) (OSN) involved in detecting the parasit- oid smell. Drosophila larvae express 23 different ORs, of which 13 are also expressed in the adult fly [19]. The identification of individual OSN responses in larvae is almost impossible, as all OSNs are colocalized in a single morphological structure, the dorsal organ. However, recording from identified adult OSNs is possible [20–24]. We therefore used a set of diagnostic odors (S1 Fig) to identify adult OSN types and afterwards performed combined gas chromatography-sin- gle sensillum recording (GC-SSR) experiments with the headspace of L. boulardi. We tested all 48 physiologically different OSN types present on the fly antennae and palps. Although the amount of active odor within the headspace was too low to be visible in the GC trace, a repeat- able and strong response was elicited from the ab10B OSN at a specific GC retention time. No other OSN type responded to the extract (Fig 2A). To identify the active compound, we col- lected a larger quantity of odors by washing wasps in dichloromethane. When repeating the GC-SSR experiments with this wash, the ab10B OSN became activated at the same retention time as found with the headspace (Fig 2B), but now with a visible GC peak. In addition, the same OSN responded to two additional compounds.
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Molecular structure and dimeric organization of the Notch extracellular domain as revealed by electron microscopy.

Molecular structure and dimeric organization of the Notch extracellular domain as revealed by electron microscopy.

Particles from classes that showed the same projection average (denoted as 1, 2 and 3 in Figures S2B and Figure S3B) were combined (summarized in Table S1). The particle images from the images of the tilted specimens were then used to calculate six individual 3D reconstructions (3 for the Drosophila and 3 for the human NECD) using the back-projection algorithm implemented in SPIDER. The orientation parameters of the particles (all particles from the images of the tilted specimens and 10% of the particles from the images of the untilted specimens) were improved over 10 refinement cycles using FREALIGN v 7.05 [21], which was also used to correct for the contrast transfer function (CTF) of the microscope. The correct defocus value for each particle image was deduced from the position of each particle in the image and the tilt angles and defocus values of the images, which were determined with CTFTILT [22]. FREALIGN was first run for one cycle using mode 3 (systematic parameter search) with an angular step of 7 u to determine initial orientation parameters for each particle relative to the starting model. The resulting parameters were iteratively refined over 9 additional cycles run in mode 1 (local parameter refinement) including data in the 200 - 10 A ˚ resolution range. The resolution of the final density maps were estimated to be 25 A ˚ using Fourier shell correlation (FSC) and the FSC = 0.5 cut-off criterion [23] (Figure S4), and the density maps were low-pass filtered to that resolution.
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Caspase-Mediated Apoptosis in Sensory Neurons of Cultured Dorsal Root Ganglia in Adult Mouse

Caspase-Mediated Apoptosis in Sensory Neurons of Cultured Dorsal Root Ganglia in Adult Mouse

In this study we examined the involvement of caspase in the apoptosis of adult sensory neurons. The sensory neurons in cultured DRG displayed cell shrinkage as well as nuclear and chromatin con- densation. Such changes have been documented as morphological features of apoptosis (9). Since apoptosis could not be conirmed by just analyz- ing the morphological changes in the nucleus and chromatin, we also used the TUNEL method which facilitates the visualization of DNA fragmentation in several apoptotic cell models (10-12). However, this method is limited because it can detect both apoptotic and non-apoptotic cells, unless it is ac- companied by other techniques (13). Altogether, observed changes in the sensory neurons provided evidence that apoptosis could be one of the reasons by which neurons perish in culture. The question of whether the present results are a relection of the cell death that occurs in response to organ culture or whether they relect events that can also occur
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Human Capital and the Recent Fall of Earnings Inequality in Brazil

Human Capital and the Recent Fall of Earnings Inequality in Brazil

where is a set of linear restrictions that transforms the unrestricted model (1) on restricted model (2). 8 In our case, the restriction implies that the age, trend and (orthogonal) time dummies are sufficient to explain the behavior of each estimated statistic order across cells and over time. Imposing the restrictions means estimating weighted least squares regressions on the grouped data, for each quantile and education group separately. This procedure will give us consistent estimates of . Under the null that the restrictions are valid, the minimized value follows a chi-square distribution with degrees of freedom equal to the number of restrictions. In order to construct the test statistics, we only have to sum up the weighted squared residuals, that is, the estimated percentiles minus the predicted values minus the orthogonal time dummies.
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The quality of castings obtained during lost-wax and Replicast CS processes in aspect of ecology

The quality of castings obtained during lost-wax and Replicast CS processes in aspect of ecology

Haratym, Dok ł adno ć wymiarowa odlewów wykona- nych w procesie Replicast CS, Archiwum Odlewnictwa rocznik 3, nr 9, Katowice 2003.. Arendarski, Niepewno ć pomiarów, Oficyna Wydaw- nic[r]

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Drosophila melanogaster Hox transcription factors access the RNA polymerase II machinery through direct homeodomain binding to a conserved motif of mediator subunit Med19.

Drosophila melanogaster Hox transcription factors access the RNA polymerase II machinery through direct homeodomain binding to a conserved motif of mediator subunit Med19.

Bimolecular Fluorescence Complementation (BiFC) Constructions corresponding to UAS-VN-Ubx, UAS-VN- AbdA and UAS-VN-HDAbdA transgenic lines are described in [32]. UAS-VN-Dfd, UAS-VN-HDUbx: Dfd and Ubx HD sequences were cloned into XhoI-XbaI sites downstream of the Venus VN fragment into the pUAST or pUASTattB plasmids described in [32]. UAS-Med19-VC, UAS-HIM-VC: Full-length Med19 coding sequences, or the internal HIM sequence generated from Med19 cDNA by PCR, were introduced as EcoRI-XhoI fragments to replace Hth coding sequences of pUaHth-VC [32]. For UAS-Med19DHIM-VC, internally deleted Med19 was generated from the full-length construct by double PCR, using the overlap extension method. The PCR-derived internal deletion product was cleaved by RsrII and XhoI, then cloned in place of the equivalent fragment of UAS-Med19-VC. All constructs were sequence-verified before fly transformation. Transgenic lines were established by classical P-element mediated germ line transforma- tion or by site-specific integration using the WC-31 integrase. Embryos were analysed as described in [32]. For BiFC in imaginal discs, late third-instar larvae of appropriate genotypes were cultured in parallel in the same environmental conditions of temperature and larval density, then were dissected at the same time and fixed in the same solution (20 9; 4% para-formaldehyde, 0.5M EGTA, 1X PBS). Wing and haltere imaginal discs were dissected and mounted in Vectashield (Vector Labs). Image acquisition was performed on a Leica SP5 using the same laser excitation, brightness/contrast and z settings. Confocal projections from at least 10 distinct wing discs per genotype were analyzed with ImageJ software.
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Cerebral Cortex Expression of Gli3 Is Required for Normal Development of the Lateral Olfactory Tract.

Cerebral Cortex Expression of Gli3 Is Required for Normal Development of the Lateral Olfactory Tract.

Correct formation of the lateral olfactory tract and specific innervation of the piriform cor- tex are prerequisites for the transmission of olfactory information [1,4,5]. Both of these pro- cesses are thought to depend on intrinsic properties of olfactory projection neurons that regulate axon outgrowth as well as environmental cues that control LOT axon navigation to the different structures of the olfactory cortex. This external control requires a number of axon guidance molecules, including EphrinA5 [6], Netrin1 [7] and Sema3B and F [8,9,10], as well as guidance by lot cells that are positioned on the telencephalic surface along the path followed by LOT axons [11]. In addition, LOT formation is controlled by several transcription factors [12,13,14], including the zinc finger transcription factor Gli3 which is expressed in progenitor cells of the dorsal and ventral telencephalon and in olfactory bulb progenitors but not in neu- rons of the piriform cortex or in mitral cells [15] (S1 Fig). Gli3 null (Gli3 Xt/Xt ) and Gli3 hypo- morphic (Gli3 Pdn/Pdn ) mouse mutants both show severe defects in the formation of the olfactory system [15,16,17]. Both mutants show no discernible olfactory bulb protrusion but form an olfactory bulb like (OB-like) structure containing mitral cells and OB interneurons in ectopic dorsal or lateral positions in the telencephalon [18]. In addition, Gli3 Pdn/Pdn mutants show apoptosis of precursor mitral cells in the OB-like structure [17] with residual surviving mitral cells creating a slender LOT [16,17]. Moreover, Gli3 Xt/Xt mutants show severe telence- phalic patterning defects resulting in the clustering of lot guidepost cells [19] and an expansion of the paleocortex [20]. Based upon these phenotypes, Gli3 could affect LOT development by controlling intrinsic OB development, the formation of environmental cues guiding LOT axons and/or the development of the LOT target area but the severity of the defects complicate the analysis of Gli3’s roles in LOT formation. To circumvent these difficulties, we made use of Emx1Cre;Gli3 fl/fl (Gli3 cKO ) conditional mutants [21] which we have previously shown to have an expanded piriform cortex [22]. These mutants formed an OB-like structure that did not protrude from the telencephalic surface but contained mitral cells and olfactory interneurons. Mitral cell axons formed a LOT which occupied a medially shifted position. LOT axons inner- vated an extended area of the piriform cortex and their collaterals penetrated deeper layers. No obvious defects were found in the expression of telencephalic guidance cues or in the formation of lot cells consistent with the formation of the LOT. However, time course analysis confirmed that the paleocortical primordium expanded from E13.5 onwards, coinciding with the arrival of the LOT axons. These findings suggest an important role for Gli3 in correctly positioning the LOT and controlling its innervation of the piriform cortex.
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The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The examination of the structure and microhardness of surface layer of C90 non-alloy steel and HS 6-5-2 high speed steel after electric arc treatment are presented in the paper. The comparison has been presented due to the similar content of the carbon in both steels. The structure of the remelted zone of the steel C90 before the conventional tempering consists of the cells, dendritic cells surrounded with the cementite, there is a plate martensite and retained austenite inside them, whereas the structure of the steel HS 6-5-2 is consistuted with cells, dendritic cells and dendrites surrounded with the eutectic system, inside of which there is a plate martensite and retained austenite. Such structure is characterized by the similar microhardness (790-800 HV0,065) and intensity of the tribiological wear. The tempering causes the decrease of the microhardness in non-alloy steel and the increase of the microhardness in high speed steel.
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The RhoGEF trio functions in sculpting class specific dendrite morphogenesis in Drosophila sensory neurons.

The RhoGEF trio functions in sculpting class specific dendrite morphogenesis in Drosophila sensory neurons.

Figure 6. Trio overexpression in class III da neurons. (A–D) Live confocal images of class III and IV dorsal cluster da neurons at the third larval instar labeled with the F-actin reporter UAS-GMA driven by the ppk-GAL4 transgene. Class III ddaA and ddaF neuron cell bodies are indicated by arrows and for clarity the class III neuron cell bodies and dendrites have been highlighted by a magenta pseudo-color trace overlay. (A) Representative image of wild-type class III da neuron displaying regularly distributed, unbranched, actin-rich dendritic filopodia (dashed line circles and high magnification image (A9)) projecting from the primary dendritic branches. (B) Full length Trio overexpression dramatically altered dendritic filopodia producing a hyper-branched, splintered morphology (dashed line circles and high magnification image (B9)). In addition, the filopodia displayed a more clustered distribution as compared to control. (C) Overexpression of the Trio-GEF1 domain increased dendritic branching overall and produced a highly similar splintered morphology on dendritic filopodia. (D) Overexpression of the Trio-GEF2 domain produces the opposite effect by reducing dendritic branching overall and leading to a dramatic decrease in the number of dendritic filopodia. (E) Quantitative analyses of the number of dendritic terminals as a measure of dendritic branching reveals no significant change with full length Trio overexpression, whereas upregulation of Trio-GEF1 dramatically leads to a significant increase in terminals both proximal and distal to the cell body, while upregulation of Trio-GEF2 leads to a significant decrease in terminals both proximal and distal to the cell body. The total n value for each neuron and genotype quantified is reported on the bar graph. Statistically significant p values are reported on the graph as follows (n.s. = not significant; *** = p,0.001). Genotypes: WT: UAS-GMA/+;ppk-GAL4/+;+. TRIO: UAS-GMA/UAS-trio;ppk-GAL4/+;+. GEF1: UAS-GMA/+;ppk-GAL4/UAS-trio-GEF1-myc;+. GEF2: UAS- GMA/+;ppk-GAL4/+;UAS-trio-GEF2-myc/+.
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The Impact of the Expansion of the Bolsa Familia Program on the Time Allocation of Youths And Their Parents Lia Chitolina Miguel Nathan Foguel Naercio Menezes-Filho

The Impact of the Expansion of the Bolsa Familia Program on the Time Allocation of Youths And Their Parents Lia Chitolina Miguel Nathan Foguel Naercio Menezes-Filho

As the multinomial model is non-linear, the marginal effect of the treatment in a DID model is not the marginal impact of the interaction between time and treatment, but the difference of the cross-differences, as described by Puhani (2012). The results of Table 7 (in terms of marginal effects) show that the BVJ has a significant effect on the probability studying and working at the same time, but not on the other outcome variables. The estimated marginal effects mean that the probability of a youngster studying and working increases by 4.2 percentage points with the BVJ, compared with a baseline of 30% in the control group in 2006. The estimated coefficients for the categories ‘studying only’ and ‘working only’ were negative but not statistically significant. It seems, therefore, that treated adolescents do not quit their jobs to study because of the program, but do both activities at the same time. This raises questions about the long run impacts of the program, since the quality of the night classes is notoriously low in Brazil.
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Fields of study and the earnings gap by race in Brazil

Fields of study and the earnings gap by race in Brazil

associated with one or more occupations, which are defined at the 4-digit level. In 2000, individuals with tertiary education are distributed across 493 occupations, of which 104 are in the groups of managers and professionals. In 2010, individuals in the sample are distributed into 433 occupations, of which 133 refer to managers or professionals’ occupational groups. Each field of study in columns (1) and (2) of Table A.1 is matched to at least one occupation in managers and professionals categories. Individuals with a bachelor’s degree working in technical, sales, service and administrative support occupations, farming, forestry, and fishing occupations, as operators, manufacturers, and laborers, or in precision production, craft, and repair are classified as having an occupation that does not require this level of education. Thus, individuals in the sample can work in occupations associated with their fields of study or in occupations unrelated to their degrees, whereas some of those in the latter group may work in occupations that do not require tertiary education.
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Synthesis Of Arts In Architecture Of Uzbekistan Of The Ancient Period

Synthesis Of Arts In Architecture Of Uzbekistan Of The Ancient Period

side), depending on the location of a sculpture in the overall composition of certain structures, on the skills of masters belonging to different art schools. In rare cases, the low relief (the sculpture in Surkh Kotal) [21], traditional for ancient Iran and less characteristic for the art of Kushan, was used. Thus, the "Bactrian sculpture was characterized by monumentality and st rict frontal position‖ [22, 90p]. But round, often three- quarter, always wall sculpture, had been rather an exception in the buildings of Greco-Bactrian period and Buddhist structures. According to references, the statue of Anahit [23] was located in the temple of Bactria before the arrival of the Greeks, and with the arrival of the Greek, the Hellenistic traditions began to play a significant role in the artistic culture of Central Asia [24]. In the Hellenistic period the sculpture was done in full volume and size, often exceeding the human scale (in Square Hall of Nisa, in the temple of Ai-Khanum in Surkh Kotal). For example, the sculpture of Ai-Khanum was two and a half times larger than the life size, this required from the masters an "excellent knowledge of modeling techniques and strengthening the clay mass" [25, 71p]. By the scale the sculptors emphasized the position of painted person in the hierarchy. Hellenistic traditions of erecting the statues of kings "were transformed over time into the objects of worship and were placed in sanctuaries‖ [26, 15p]. In Bactria there existed and were for a long time exercised the temples of Hellenic Gods (Temple of Dioscurus in Dilberdjin), "visited by both local descendants of Greek colonists and the Hellenized part of local population" [27, 82p]. In all probability, Greek deities were placed there (for example, in the area of
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The TollNF- κB signaling pathway is required for epidermal wound repair in Drosophila

The TollNF- κB signaling pathway is required for epidermal wound repair in Drosophila

Fig. 3. Remodeling of E-cad::GFP at the wound edge fails in Dif dl mutants. (A–H) Ventral epidermis of embryos at stage 15 expressing E-cad::GFP and membrane::mCherry. A, B, D–F, and H show E-cad::GFP, whereas C and G show membrane::mCherry. Images are taken with identical settings at 5 min after wounding of wild type (A–D) and Dif dl (E–H). (B, C, F, and G) are high-magnification images of the wound edge in wild-type and Dif dl embryos (boxed regions in A and E). In wild type, wound-edge membranes have low levels of E-cad::GFP (A; B, arrows) compared with cellular junctions at a distance from the wound. In wound-edge cells, E-cad::GFP is present as apical puncta (B, arrowheads) at contact points between the cells. In Dif dl, all epidermal cells, at the wound edge and far from the wound, have high levels of E-cadherin (E; F, arrows). Wound-edge membranes are outlined by membrane::mCherry (C and G). Asterisks mark the wound. (D and H) YZ cross sections of the epidermis (apical side is up). Dashed lines in A and E mark the positions of the cross-sections. The graphs show the fluorescence intensity profiles of E-cad::GFP in these YZ cross-sections. The wound area is shaded; the wound margin is marked with a red dashed line. Both wild- type and Dif dl embryos display apical localization of E-cad::GFP (arrowheads in D and H). Wild-type cells have low levels of E-cad::GFP at the wound edge, whereas Dif dl cells retain high levels of fluorescence. (I) Schematic representation of the wound-edge membranes (green lines) and AJs (blue lines) used for the measurements and quantification of E-cad::GFP fluorescence shown in J and K. (J) Ratio of E-cad::GFP at wound-edge membranes versus E-cad::GFP at AJs away from the wound in wild type and in Dif dl. In wild type, this ratio is significantly lower (0.685 ± 0.050) than in Dif dl (1.133 ± 0.076), P = 2.7 x 10 −5
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Analysis Of Lean Accounting JIT And Balance Scorecard In The Companys Lean Manufacturing

Analysis Of Lean Accounting JIT And Balance Scorecard In The Companys Lean Manufacturing

customer response times.[1]. Lean manufacturing can also purposed to lean effort and wasting time to increase goal production. By disspeared all 0f them wastes such as time, effort and finance. The company can competition with the other companies. And face uncertaintly in the future. This terms supported. Wang [2011] Lean manufacturing is the production of goods using less of everything compared to mass production: less waste, less human effort, less manufacturing space, less investment in tools, and less engineering time to develop a new product.[9] furthermore Boczko [2007] said that Lean manufacturing is a generic process management philosophy derived mostly from the Toyota Production System (TPS) as well as other industrial best practices. Lean manufacturing is renowned for its focus on reduction of Toyota’s original ―seven wastes‖ in order to improve overall customer satisfaction [9]. Lean manufacturing has good designed to the company that especially in the manufacturing field. Furthermore Hansen [2007] described that Lean manufacturing is thus an approach designed to eliminate waste and maximize customer value. It is characterized by delivering the right product, in the right quantity, with the right quality (zero-defect), at the exact time the customer needs it and at the lowest possible cost [7]. Line manufacturing can be priority by company to reach target achievement production appropriate costumer demand. Cesarony [2014] has opinion that Zero setup times, zero defects, zero inventories, zero waste, producing on demand, increasing a cell’s production rates, minimizing cost, and maximizing customer value represent ideal outcomes that a lean manufacturer seeks.[17]. In other hand lean manufacturing has
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Description and Analysis of Genetic Diversity among Squash Accessions

Description and Analysis of Genetic Diversity among Squash Accessions

The identification and utilization of the diverse germplasm is the central issue in plant breeding. Thorough knowledge of the genetic diversity of a crop is necessary for the parental selection that maximizes the genetic improvement. More accurate and complete descriptions of the genotypes and patterns of the genetic diversity could help determine future breeding strategies and facilitate the introgression of diverse germplasm into the current commercial squash genetic base. From all the results obtained, it is clearly evident that there is a considerable variation among the squash accessions, for both the morphophysiological and molecular characteristics. More specifically, as far as the morphology was concerned, the accessions significantly differed in the flower, fruit and seed characteristics. In terms of the response to the pathotypes of F. oxysporum, there was a great variation ranging up to complete resistance. Also, the PCA analysis revealed high correlation of the resistances to the two pathotypes (r = 0.66, P = 0.001, data not shown). At that point, a function character added to the genetic diversity procedure should be mentioned. The usefulness of the resistant accessions offers benefits to breeders by providing a logical general strategy in identifying the best source. Besides, it provides a possibly useful resource by applying a parallel program checking the compatibility of the resistant accessions as rootstocks, enriching thus a friendliness to the environment cultivation system. In the case of the RAPD markers, a very high genetic variation was observed among the indigenous squash accessions, in concordance with the considerable variation revealed at the morphophysiological level. The notably high level of the polymorphism among the accessions (97.44%) was expected for the different Cucurbita species. Similar high level of the polymorphism (98.28%) was also reported among different Ocimum species (Singh et al., 2004). The evaluation of 40 morphophysiological characteristics revealed great variation among the accessions and resulted in seven principal components covering more than 80% of the total variation. The first two principal components were able to explain a cumulative percentage of only 45.79% of the total variation. According to PCA, the accessions formed two distinct groups, with the codes 221 and 224 to be clearly separated in
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Regulation of spike timing-dependent plasticity of olfactory inputs in mitral cells in the rat olfactory bulb.

Regulation of spike timing-dependent plasticity of olfactory inputs in mitral cells in the rat olfactory bulb.

It has been reported that stimulation of ON induced long- lasting depolarizations (LLDs) that lasted as long as several seconds [30,35,36,37]. The LLDs may only occur synchronously in cells Figure 3. STDP of excitatory olfactory sensory inputs to MCs. (A) Schematic of experimental configuration. Whole-cell recording of a single MC during the application of an extracellular stimulation in an associated glomerulus (the upper dotted line circle) that activated presynaptic excitatory sensory inputs. (B) Potentiation of EPSPs in MCs by a +30 ms pairing (Dt = +30 ms, repeated 60 times). The induction protocol for LTP is depicted on top of the arrow. An EPSP evoked by an extracellular stimulation was paired with a short burst of three APs at 50 Hz elicited by current injections into the postsynaptic cell. The depicted pairing protocol resulted in the potentiation of the EPSP amplitude. The EPSPs averaged at the indicated times are shown on top of the graph. (C) Summary of the changes in the EPSP amplitude following a +30 ms pairing protocol (n = 6; p,0.001). (D) STDP plot showing the critical time window for synaptic potentiation and depression of excitatory sensory inputs. The percentage of changes in the EPSP amplitude of synaptic inputs lasting 10 min after the repetitive stimulation was plotted against the time of the inputs (defined by the onset time of the EPSP relative to the onset of the first AP in the burst) [16]. ** p,0.01, compared with baseline. (E) Statistical plot showing the ISI when Dt was set to +30 and 250 ms (n = 6), respectively. (F) Depression of EPSPs in MCs by a 250 ms pairing (Dt = 250 ms, repeated 60 times). (G) Summary of the changes in EPSP amplitude following a 250 ms pairing protocol (n = 6; p,0.001).
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Nutritional plasticity and evolutionary divergence in the Drosophila ovary

Nutritional plasticity and evolutionary divergence in the Drosophila ovary

When we look carefully at the natural world, we cannot help but notice the wonder of living things. From the astonishing beauty and diversity of species that inhabit even some of the most inhospitable places on Earth to the spectacular and intricate machinery of the cells that can only be appreciated at the molecular level. But, how did such diversity and complexity come to be? The theory of evolution developed by Charles Darwin and Alfred Russel Wallace drastically changed our perception of how life forms diversify. After the widely scientific acceptance of the theory of evolution during the 1930s and 1940s – when empirical and theoretical work recognized genes as the unit of evolutionary change by means of natural selection –, “most evolutionary geneticists would agree that the major problems of the field have been solved” (Charlesworth, 1996). Yet, an emerging paradigm of how living things diversify has recently put forward by researchers from different disciplines, including genetics, developmental biology, physiology and ecology. This comprehensive view argues that changes that occur during an organism’s development as a result of the delicate interplay between genes and the external environment should be recognized as causes of evolutionary change (West-Eberhard, 2003; Stearns, 1989; Moczek, 2012; Laland et al., 2014). From this broader vision of evolution, a particularly exciting concept has resurged that enhances our understanding of the origins of phenotypic variation; that of developmental plasticity. This widespread phenomena refers to the ability of an organism to change its developmental trajectories in response to environmental variation and generate a range of phenotypes without altering its genome (West-Eberhard, 2003; Stearns, 1989). Such environmentally-induced changes were once seen as nuisance and oddities that complicated evolutionary and developmental studies, but within the last decade, a renewed interest in how developmental plasticity might contribute to evolutionary diversification has grown tremendously (West- Eberhard, 2003; Stearns, 1989; Wund, 2012; Laland et al., 2014; Beldade et al., 2011).
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Inducible and targeted deletion of the ERK5 MAP kinase in adult neurogenic regions impairs adult neurogenesis in the olfactory bulb and several forms of olfactory behavior.

Inducible and targeted deletion of the ERK5 MAP kinase in adult neurogenic regions impairs adult neurogenesis in the olfactory bulb and several forms of olfactory behavior.

Several factors may contribute to this controversy including the specificity of methods used to ablate or suppress adult neurogen- esis. Although effective at suppressing adult neurogenesis, x- irradiation or anti-mitotic drugs are not specific for adult-born neurons. They target all dividing cells, may alter the neurovascular niche important for adult neurogenesis, and induce neural inflammation. The side effects intrinsic to these methods may be confounding factors contributing to inconsistent behavior results. Indeed, two studies using similar protocols for AraC administra- tion to the lateral ventricle to suppress adult neurogenesis yielded opposite conclusions concerning a role for adult neurogenesis in long-term olfactory memory [21,34]. Studies using traditional knockout of genes important for neurogenesis are also useful, but their interpretations are limited by widespread abnormalities of brain structure or compensatory effects elicited during develop- ment. Transgenic expression of a lethal gene, such as diphtheria toxin or thymidine kinase [40,44], to kill adult-born neurons is more specific to adult neural stem/progenitor cells. However, large amounts of cell death in the SVZ-RMS-OB axis may interfere with normal olfactory function. These technical issues make it difficult to establish a definitive connection between adult neurogenesis and olfactory behavior.
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